Tanks are very large, very strong, and very angry. Their particular and most prominent mutation is their bulging muscles. In the same way the reavers' bones began to grow at an accelerated rate, so did the tanks' muscles. Because their muscles grew so much so fast their skin is covered in rips and scars.
The only thing tanks are concerned with is killing. Killing what? Everything. They have no allies and will just as soon rip apart a zomb as they will a survivor. They know nothing but pure rage and everything is cause for them to be pissed off. You're in their line of sight? Rage. There's a dog pissing on a fire hydrant? Rage. You're within a five mile radius of them? Pure, unadulterated, god-hating rage.
They do not think, they simply attack. They're not too intelligent, and aren't so big on navigating through rooms or opening doors. Instead, they simply go through whatever's in their way.
Yay original monsters.
